From the Guidelines
For patients with sickle cell disease requiring chronic transfusions, automated red cell exchange (RCE) is suggested over simple transfusion due to its potential benefits in reducing iron overload and improving HbS suppression, as stated in the 2020 American Society of Hematology guidelines 1. When deciding between a simple transfusion and an exchange transfusion for a patient with sickle cell disease (SCD), the severity of the complication and the patient's clinical status are crucial factors.
- Simple transfusions are generally used for less severe complications such as symptomatic anemia, preoperative preparation, stroke prevention, and managing acute chest syndrome with mild hypoxia.
- Exchange transfusions, on the other hand, are reserved for more critical situations like severe acute chest syndrome, stroke, multi-organ failure, severe acute intrahepatic sequestration, and refractory painful crises. The choice between these two procedures also depends on the patient's hemoglobin level, clinical severity, and the urgency of the situation.
- Simple transfusions are easier to perform but can increase blood viscosity if the hemoglobin rises too high.
- Exchange transfusions, particularly automated RCE, more effectively reduce the percentage of sickled cells without increasing viscosity, and they offer the added benefit of reducing iron overload compared to simple transfusions 1. According to the American Society of Hematology 2020 guidelines, for patients receiving chronic transfusions, either red cell exchange with isovolemic hemodilution (IHD-RCE) or conventional RCE is suggested, with the consultation of a hematologist and transfusion medicine specialist advised to assess safety for the individual patient and technical specifications 1. In practice, the decision to use a simple transfusion versus an exchange transfusion should prioritize the reduction of morbidity and mortality, and improvement in quality of life, with exchange transfusions being preferred for their ability to more effectively manage severe complications and reduce long-term risks associated with SCD 1.
From the Research
Transfusion Techniques for Sickle Cell Disease
The decision to use a simple transfusion versus an exchange transfusion for a patient with sickle cell disease (SCD) depends on various factors, including the severity of anemia, the level of hemoglobin S (HbS), and the presence of complications such as acute chest syndrome or stroke.
- Simple transfusion may be utilized in situations where correction of severe anemia and reduction in HbS may be achieved without removal of RBCs 2.
- Exchange transfusion, either manual or automated, is useful in situations where a rapid and drastic HbS reduction is indicated, such as in severe complications like acute stroke or acute chest syndrome 2, 3.
- Partial manual RBC exchange allows for larger changes in the ratio of HbS to HbA compared to simple transfusion, and is often used in situations where a moderate reduction in HbS is required 2.
Indications for Transfusion
The indications for transfusion in SCD include:
- Acute complications such as acute chest syndrome, stroke, and severe acute anemia 4, 5, 3.
- Primary and secondary stroke prevention 4, 3.
- Preoperative transfusions to reduce the risk of perioperative complications 4, 3.
- Pregnancy, to reduce the risk of maternal and fetal complications 4, 3.
- Curative therapies, such as bone marrow transplantation 2.
Choice of Transfusion Technique
The choice of transfusion technique depends on the individual patient's needs and the specific clinical scenario.
- Simple transfusions are often effective in managing acute chest syndrome, and may be preferred in situations where a less invasive intervention is desired 5.
- Exchange transfusions, either manual or automated, are typically used in situations where a rapid and drastic reduction in HbS is required, such as in severe complications like acute stroke or acute chest syndrome 2, 3.